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31.
酱油渣中提取油脂和黄酮   总被引:1,自引:0,他引:1  
[目的]探讨从酱油渣中提取油脂和黄酮类物质的最佳工艺参数,为酱油渣资源的进一步开发利用提供基础数据.[方法]在单因素实验的基础上,采用正交设计方法,研究各因素对油脂和黄酮提取率的影响.[结果]研究表明,油脂提取最佳条件为:酱油渣与异丙醇比例为1:13,超声温度50℃,超声时间30 min,该条件下油脂的提取率为34.76%;从脱脂酱油渣中提取黄酮的最佳条件为:50%乙醇、料液比1:30、超声时间15 min、提取温度60℃,在此条件下,黄酮的提取量为2.471 0 mg/g.[结论]利用超声波辅助提取技术从酱油渣中提取油脂和黄酮可行.  相似文献   
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As point-of-care ultrasound (POCUS) invades medical specialties, more students covet earlier ultrasound (US) training programs in medical school. Determining the optimal placement and format in the curriculum remains a challenge. This study uses student perceptions and confidence in interpreting and acquiring images to evaluate the effectiveness of an US curriculum and assesses their performance on US content. A unique US curriculum was incorporated into first-year clinical anatomy at Tufts University School of Medicine (TUSM). Students completed surveys evaluating changes in US confidence and perceptions. Mean ratings on pre- and post-surveys were compared using Mann–Whitney U tests. Performance on US examination questions was evaluated. Two independent evaluators coded narrative responses and NVivo software was used to identify common themes. Two hundred eleven students completed the US curriculum. Students reported higher post-curriculum mean confidence ratings on US comprehension, operation, image acquisition, artifact recognition, and normal image interpretation (P < 0.0001). US reinforced anatomy concepts and clinical correlates (9.56, ±0.97 SD; 9.60, ±1.05). Students disagreed with items stating learning US is too difficult (1.2, ±2.2) and that it interferes with learning anatomy (0.68, ±1.7). Students scored above passing on practical US knowledge questions, supporting survey data, and the relation to learning spatial relationships. Qualitative analysis identified seven major themes and additional subthemes. Limited integration of US breaks barriers in students' perceptions and confidence in performing POCUS. The TUSM US curriculum is a natural marriage of anatomy and POCUS applications, serving as a template for medical schools.  相似文献   
34.
超声波在植物有效成分提取中的应用   总被引:41,自引:0,他引:41  
简述了超声波作用的基本原理 ,对超声波在提取植物有效成分中的应用和研究进展进行了综述 ,指出超声提取具有提出率高、速度快且不改变有效成分的结构等优点 ,讨论了超声波提取中应注意的问题 ,为超声提取研究提供参考  相似文献   
35.
Ultrasound (US) can enhance anatomy education, yet is incorporated into few non‐medical anatomy programs. This study is the first to evaluate the impact of US training in gross anatomy for non‐medical students in the United States. All 32 master's students enrolled in gross anatomy with the anatomy‐centered ultrasound (ACUS) curriculum were recruited. Mean Likert ratings on pre‐ and post‐course surveys (100% response rates) were compared to evaluate the effectiveness of the ACUS curriculum in developing US confidence, and gauge its impact on views of US. Post‐course, students reported significantly higher (P < 0.001) mean confidence ratings in five US skills (pre‐course versus post‐course mean): obtaining scans (3.13 ±1.04 versus 4.03 ±0.78), optimizing images (2.78 ±1.07 versus 3.75 ±0.92), recognizing artifacts (2.94 ±0.95 versus 3.97 ±0.69), distinguishing tissue types (2.88 ±0.98 versus 4.09 ±0.69), and identifying structures (2.97 ±0.86 versus 4.03 ±0.59), demonstrating the success of the ACUS curriculum in students with limited prior experience. Views on the value of US to anatomy education and to students' future careers remained positive after the course. End‐of‐semester quiz performance (91% response rate) provided data on educational outcomes. The average score was 79%, with a 90% average on questions about distinguishing tissues/artifacts, demonstrating positive learning outcomes and retention. The anatomy‐centered ultrasound curriculum significantly increased confidence with and knowledge of US among non‐medical anatomy students with limited prior training. Non‐medical students greatly value the contributions that US makes to anatomy education and to their future careers. It is feasible to enhance anatomy education outside of medical training by incorporating US. Anat Sci Educ 10: 348–362. © 2016 American Association of Anatomists.  相似文献   
36.
简要介绍超声波探伤仪。以主机控制单元为例,从器件的选择、源文件设计、器件实现过程介绍CPLD技术,最后给出CPLD器件的应用结论。  相似文献   
37.
Ultrasonography is increasingly used in medical education, but its impact on learning outcomes is unclear. Adding ultrasound may facilitate learning, but may also potentially overwhelm novice learners. Based upon the framework of cognitive load theory, this study seeks to evaluate the relationship between cognitive load associated with using ultrasound and learning outcomes. The use of ultrasound was hypothesized to facilitate learning in anatomy for 161 novice first‐year medical students. Using linear regression analyses, the relationship between reported cognitive load on using ultrasound and learning outcomes as measured by anatomy laboratory examination scores four weeks after ultrasound‐guided anatomy training was evaluated in consenting students. Second anatomy examination scores of students who were taught anatomy with ultrasound were compared with historical controls (those not taught with ultrasound). Ultrasound's perceived utility for learning was measured on a five‐point scale. Cognitive load on using ultrasound was measured on a nine‐point scale. Primary outcome was the laboratory examination score (60 questions). Learners found ultrasound useful for learning. Weighted factor score on “image interpretation” was negatively, but insignificantly, associated with examination scores [F (1,135) = 0.28, beta = ?0.22; P = 0.61]. Weighted factor score on “basic knobology” was positively and insignificantly associated with scores; [F (1,138) = 0.27, beta = 0.42; P = 0.60]. Cohorts exposed to ultrasound had significantly higher scores than historical controls (82.4% ± SD 8.6% vs. 78.8% ± 8.5%, Cohen's d = 0.41, P < 0.001). Using ultrasound to teach anatomy does not negatively impact learning and may improve learning outcomes. Anat Sci Educ 10: 144–151. © 2016 American Association of Anatomists.  相似文献   
38.
Abstract

The purpose of this study was to investigate changes in ankle joint stiffness and the associated changes in the gastrocnemius muscle and tendon due to static stretching. Seven healthy male participants lay supine with the hip and knee joints fully extended. The right ankle joint was rotated into dorsiflexion from a 30° plantar flexed position and the torque measured by a dynamometer. The ankle joint was maintained in a dorsiflexed position for 20 min (static stretching of the calf muscles). We performed surface electromyography of the medial and lateral gastrocnemii, the soleus, and the tibialis anterior of the right leg to confirm no muscle activity throughout static stretching and the passive test (passive dorsiflexion). During static stretching, the ankle joint angle and elongation of the gastrocnemius were recorded by goniometry and ultrasonography, respectively. Tendon elongation of the gastrocnemius was calculated based on the changes in the ankle joint angle and muscle elongation. In addition, the relationships between passive torques and ankle joint angles, and elongation of muscle and tendon, were examined before and after static stretching. The ankle dorsiflexion angle and tendon elongation increased significantly by 10 min after the onset of static stretching, while there was no further increase in muscle length. In addition, ankle dorsiflexion angle and tendon elongation at an identical passive torque (30 N · m) increased significantly (from 24±7° to 33±5° and from 17±2 mm to 22±1 mm, respectively) after static stretching. However, muscle elongation was unchanged. In conclusion, the current results suggest that an increase in the ankle joint dorsiflexion angle due to static stretching is attributable to a change in tendon not muscle stiffness.  相似文献   
39.
Abstract

The purpose of this study was to investigate the time course of the changes of muscle-tendon mechanical properties and the function responses of the plantar flexor muscles following 5?×?60?s of static stretching.

Fourteen healthy volunteers were tested on four separate days in a random order with three different rest times (0, 5, 10?min) after 5?×?60?s of stretching or following a control period without stretching. During each test, the dorsiflexion range of motion (RoM), passive resistive torque (PRT), and maximum voluntary contraction (MVC) were measured with a dynamometer. Ultrasonography of the gastrocnemius medialis (GM) muscle-tendon junction displacement and motion capture allowed us to determine the length changes in the tendon and muscle, respectively, and hence to calculate their stiffness.

We observed an increase in RoM and decrease in MVC at 0, 5, and 10?min post-stretching. This could be attributed to an increase in muscle elongation which lasted at least 10?min. A decrease in muscle-tendon stiffness was observed immediately, but not 5 or 10?min after the stretching. A decrease in PRT and muscle stiffness was observed up to 5?min after the stretching. No changes were detected in tendon stiffness or in any variable in the control group.

The effects of a 5?×?60?s static stretching exercise changes the muscle-tendon functions (RoM, MVC), which are related to mechanical changes of the muscle but not the tendon structure, respectively. Although the functional changes last for at least 10?min, changes in muscle stiffness were only observed up to 5?min after the stretching exercise.  相似文献   
40.
在运动训练中,优秀高山滑雪运动员保持较好的体质、身体形态学、跟骨超声骨量对提高高山滑雪项目运动员的运动成绩是非常有好处的。采用文献资料法、测试法、数理统计法对优秀高山滑雪运动员体质、身体形态学与跟骨超声骨量现状进行研究,为其科学运动训练提供借鉴。结果显示:高山滑雪运动员体重、身体质量指数、体脂率、瘦体重显著低于对照组,身高与对照组差异不显著;高山滑雪女子运动员体脂率显著低于对照组,瘦体重显著高于对照组,其他各项指标与对照组差异不显著;运动员体质方面男子高山滑雪运动员握力体重指数显著低于体育大学生,其他各项指标显著高于对照组,女子高山滑雪运动员体质各项指数显著高于对照组;高山滑雪运动员跟骨超声骨量参数均显著高于对照组。  相似文献   
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